CVE-2020-9818Apple iOS, iPadOS, and watchOS Out-of-Bounds Write Vulnerability

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 13.5 and iPadOS 13.5, iOS 12.4.7, watchOS 6.2.5. Processing a maliciously crafted mail message may lead to unexpected memory modification or application termination.

8.8 HIGHEPSS 2.34%⚡ Known Exploited (CISA KEV)NVD: Analyzed

Last updated: 2026-06-17 03:28 UTC

OverviewCVSS details

8.8HIGHCVSS 3.1

Score source: NVD
NVD status: Analyzed
Published: Jun 9, 2020
Assigner: apple

Affected

iOS (Apple)

Versions: before iOS 13.5 and iPadOS 13.5
Fixed in: iOS 13.5 and iPadOS 13.5

+2 more products →

Exploitation

Public exploit: None listed
CISA KEV: Listed · Nov 3, 2021
KEV due date: May 3, 2022
Ransomware use: Unknown
SSVC: Exploitation active · Automatable no · Impact total

EPSS · FIRST, scored Nov 6

2.34%chance of exploitation in 30 days

Higher than 83.71% of CVEs

CVSS 3.1 · NVD

8.8High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

CVSS 2.0 · NVD

6.8Medium

AV:N/AC:M/Au:N/C:P/I:P/A:P

Attack vector: Network
Attack complexity: Medium
Authentication: None
Confidentiality impact: Partial
Integrity impact: Partial
Availability impact: Partial

NVD status: Analyzed

Overview Affected Products References

NVD CVE.org

Overview

Severity

Score	Severity	Version	Vector String
8.8	HIGH	3.1NVD	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8	MEDIUM	2.0NVD	AV:N/AC:M/Au:N/C:P/I:P/A:P

CISA required action

⚡ Known exploited · remediation due May 3, 2022

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Details

CVE ID: CVE-2020-9818
Status: Analyzed
Assigner (CNA): apple
Published: Jun 9, 2020
Last modified: 2026-06-17 03:28 UTC
Weaknesses: CWE-787

Sources

Refreshed hourly from the sources above. Last fetched 2026-11-07 14:06 UTC.